William g



(No Model.)

W. G. RENDALL.

CUTTER HEAD.

No. 335,309. Patented Feb. 2, 1886.

INVENTOR ATTORNEYS.

UNITED STATES PATENT OFFICE.

XVILLIAM G. RENDALL, OF PORTLAND, OREGON.

CUTTER-H EAD.

SPECIFICATION forming part of Letters Patent No. 335,309, dated February2, 1886.

Application filed September 3, 1885. 5crialNo.170,0Tfi. (No model.)

To all whom it may concern:

Be it known that 1, WILLIAM G. RENDALL, of Portland, in the county ofMultnomah and State of Oregon, have invented a new and ImprovedSectional Spiral Cutter-Head, of which the following is a full, clear,and exact description.

My invention relates to rotatable cutterheads, adapted more particularlyfor use in felling trees and for cutting off driven piles while buildingwharves or other structures, the cutter-head being adapted to be carriedby any suitable frame having pulleys and belts for rotating it as it ispressed to the work.

The invention consists in certain novel features of construction andcombinations ofparts of the cutter-head, all as hereinafter fullydescribed and claimed.

Reference is to be had to the accompanying drawings, forming part ofthis specification, in which similar letters of reference indicatecorresponding parts in all the figures.

Figurel is a side elevation of the central portion of a spiralcutter-head made in accordance with my invention, and with reverse orright and left hand spirals, and showing also one end portion of thecutter-head partly broken away. Fig. 2 is an enlarged crosssectionalelevation of the cutter-head shown in Fig. l and drawn full size. Fig. 3is aside elevation of the central part of aspiral cutterhead made withright and left hand spirals, but with a different form of cutting-toothto that shown in Fig. 1. Fig. 4 is an enlarged cross'sectional elevationof the cutter-head shown in Fig. 3 and drawn full size. Fig. 5 is aperspective view of one of the tooth-holding heads or sections of thecutter-head. Fig. 6 is a perspective view of one of the teeth usedin thecutter-head shown in Figs. 1 and 2. Fig. 7 is a perspective view of oneof the toothed cutters used in the head shown inv Figs. 3 and 4; andFig. 8 is a diagram in smaller scale, illustrating a complete double orreverse spiral cutter-head.

The letter A indicates the shaft of the cutterhead, onto which areplaced by their central ring portions, 11, the cutter or tooth holdingheads or sections B, which may vary in numher according to the desiredlength of the cutter-head, the sections being placed upon the shaft A,side by side, so as to be clamped tightly together by nuts 0 O, threadedupon the opposite ends of the shaft, and between said nuts and the outeror end tooth=holding sections, B, I prefer to interpose heavy collars D,which are of about the same diameter as the sections B, and serve asclamps to hold the sections rigidly together on the shaft A, to whichthe rings 1) of the sections will be quite snugly fitted. Thetooth-holding sections B have opposite end parts or wings B B, whichhave flat opposite sides or faces b b, lying in the same plane with theopposite edges of their ring portions 1), and these opposite faces aredisposed one in advance of the other, thereby forming beveled faces I)b" at opposite edges of the end parts, B, of each section B, so thatwhen the sections are clamped together on their shaft A, with their endsB advanced one on the other, the opposite beveled faces I) b of theirend parts will form the practically smooth opposite faces of acontinuous helical web ext-ending around and along the shaft A, eitherto the right or left hand. depending on the way in which the faces 121)" are beveled with relation to the flat side faces of the sections B.The helical web thus formed is comparatively thick and heavy, so as togive substantial supportto the teeth or cutters set into the sections B,as presently described, and at the same time ample clearance room isafforded for the escape of the sawdust or chips produced by the teeth orcutters through the spiral space formed outside of the ring portions bof the sections.

About at the centers of the opposite faces I) I) of the end parts, B, ofeach section B are formed radial recesses E F, respectively, whichrecesses have notches G- formed in their opposing side edges, so thatthe tongues H formed on the tangs I of either style of cutting-tooth Jor K may enter the notches G, while the tangs I rest in the main partsof the recesses. The recesses E F are in depth but one ha1f thethickness of the tangs I of the teeth, and when the sections B areproperly disposed along the shaft A to form the spiral web, as aboveexplained, the opposite recesses E F of the adjacent sections B willcoincide,

as shown at the extreme left of Fig. 1, so that when the teeth areplaced in the recesses their t-angs I serve as dowels to look into theopposing faces of ends B or into each section B at four differentplaces, to prevent the sections from slipping around separately on theshaft, and thus preserve the integrity of the spiral web formed by theend parts, B, of the sections, the opposite clamping-collars D and nut 0serving to hold the sections firmly to each other, face to face, to holdthe teeth in place laterally in the cutter-head. The teeth J or K haveprojecting shoulders, as at j k, respect: ively, at opposite faces ofthe tangs-I, so as to increase the thickness of the heads or body partsof the teeth over that of the t'angs at each side for a distance equalto one-half the space between the next adjacent recesses E F, in whichthe tangs are held, and thereby allowing the bodies of the teethwl'1ichbodies are of the same thickness as the cutter-head sections Bto toucheach other at their side faces and mutually support each otherlaterally, and form practically a continuous cutti ngspiral around thecutter-head for its whole' length.

It is obvious that the interlocking of the tongues H of the teeth-tangswith the notches G of the sections B will prevent displacement of theteeth from the cutter-head by centrifugal force as the cutter revolves,and the tongues and notches, which are spaced uniformly, also allow theshanks of the teeth to be set out farther in the recesses E F ofsections B as the cutting points or edges are worn away or reduced byrepeated sharpenings, so that the original peripheral diameter of thecutterhead may be preserved until the teeth are practically worn out,and broken or wornout teeth can readily be replaced by new ones.

I make the teeth J with forwardly-projecting lugs j at the bases oftheir body parts, said lugs giving the lap of one tooth on the next atthe sides of the teeth, and also giving strength to the teeth; and whensaid teeth J are first set into the cutter-head sections B the lugs jrest on the extremities of the end parts, B, of said sections. (See Fig.2.)

The outer or body parts of theteeth K have a peculiar form, being madewith shoulders at each side, overhanging the tang I, and also with lugsk, projecting opposite ways from the tang and lengthwise of the body,which is of like thickness throughout, so as to have substantial lateralsupport by the body parts of the teeth at each side of it, the lap ofthe body part of one tooth on the body part of the next tooth beingabout one-half the length of the body parts of the teeth. The body partsof the teeth K are, like those of the teeth J, of the same thickness asthe sections B of the cutter-head, between and by which their tangs areheld, and when these teeth K are first put in place their shoulders 70and end lugs, k, rest on the extremities of the end parts, B, of thesections B, as shown in Fig. 4. The projecting lugs k k of the tooth Kafford room on the body of the tooth for the two cutting points ordouble cutters k If, which are set one in advance of the other, and soas to project radially from diagonally-opposite side parts of the bodyof the tooth. For a righthand spiral, the front cutter, 70 will be setat the right-hand side of the tooth, and the rear cutter, k will be setat the left-hand side of the tooth, as shown in Fig. 7 and at thelefthand end of Fig. 3,while for lefthand spirals the front cutter, it",will be at the left-hand part and the rear cutter, 70 at the right-handpart of the tooth, and as indicated at the right hand end of Fig. 3.

The construction of theteeth K with double cutters k k, and whetherarranged for right or left hand spirals, leaves a clear space the widthof the thickness of two of the cutters or the whole thickness of thebody parts of the cutters between the lines of teeth, ranginglongitudinally and parallel to the axis of the cutter-heador, in otherwords, between the forward cutter, It, of one tooth K and the rearcutter, is, of the next adjacent tooth K; hence ample clearance-room isafforded for the escape of the sawdust or chips produced by the cutters,and the teeth will not clog when at work.

The teeth J will serve without change of form for either right or lefthand spirals, as

seen in Fig. 1.

Gutter-heads with their spiral web running one way, and either right orleft handed for the whole length of the heads, will answer for lightwork; but for heavy work-such as felling large trees or cutting heavypilesI prefer to make the cutter-heads with opposite or right and lefthand spirals meeting at the center of the cutter-head,where they form orare provided with a cutter, and which construction is shown in Figs. 1,3, and 8, the latter figure being in the nature of a diagram view inwhich the cutter-head appears solid, and

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without the inserted teeth or cutters in its v spiral webs.

The chief advantages of the double or reverse spiral cutters are, thatthe chips or cuttings are thrown to opposite sides of the center of thecutter, and the teeth thus will clear themselves more readily, and inheavy cutting the cutter-head will have no tendency to draw itssupporting-frame to one side. Where the reverse spirals meet at thecenter of the cutter-head, and when the teeth J are employed, one ofsaid teeth will form the central cutting-point, L, as shown in Fig. 1,and when theteeth K are used I may use as a center cutter, L, a doubletooth, Z, or one of the teeth K may be employed; but the tooth I, havingcutting-edges the full width of the body part of the tooth, is atpresent deemed preferable.

The shaft A will have end extensions, a a, by which it will be fitted inany approved way to socket-bearings, to which the driving-pulleys of thecutter-head will be connected.

I propose to make the central shaft, A, of steel or iron, and thetooth-holding sections B and the teeth J or K of solid steel, so thatthe cutter-head will have ample strength to meet all strains broughtupon it by contact with hard knots in the timber operated upon.

The tangs of the teeth or cutters J or K may be made larger one or bothways at or toward their extremities, so as to underlock or dovetail withthe recesses in the wings or ends of the cutter-head sections; but thisconstruction would not allow the cutters to be set out farther when wornby sharpening, and as herein before explained; hence the constructionwith tangs I, having teeth H, adapted to interlock with all or anynumber of the notches G in the recesses E F, is preferred.

It is obvious that the notches G may be formed along one edge or faceonly of the recesses E F, and the tangs I of the teeth or cutters J or Kthen would have teeth Harranged to interlock with the recess, notches,or corrugations.

The right and left hand spiral webs shown in the drawings are double 4thread spirals, which are preferred, the pitch of the spirals beingabout four inches for a cutter-head four inches in diameter; butsingle-thread spirals may be used, if desired.

Having thus described my invention, whatI claim as new, and desire tosecure by Letters Patent, is-

1. A cutter head comprising a series of transversely ranging sectionshaving end wings or parts which form a spiral web around and along thecutter-head when the sections are clamped together face to face, andsaid wings or end parts of the sections formed with recesses in theiropposite faces coinciding with recesses in the faces of the wings or endparts of the next adjacent sections when the sections are disposed toform the spiral web, and teeth or cutters having tangs fitting thesockets formed by these coincidingface recesses of the sections, saidtangs forming dowels to preserve the integrity of the spiral web whenthe sections are clamped together, substantially as herein set forth.

2. A cutter head comprising a series of transversely ranging sectionshaving end wings or parts radiating from a central ring or collar, andadapted to form a spiral web around and along the cutter-head when thesections are clamped together face to face, a shaft passing through therings, clamping devices on the shaft for binding the cutterhead sectionstogether, and teeth or cutters on the spiral web, substantially asherein set forth.

3. A cutter head comprising a series of transversely ranging sectionshaving end wings or parts radiating from a central ring or collar, andadapted to form a spiral web around and along the cntterhead when thesections are clamped together face to face, and said wings or end partsformed with recesses in their op posite faces coinciding with recessesin the faces of the wings or end parts of the next adjacent sectionswhen the sections are disposed to form the spiral web, teeth or cuttershaving tangs fitting the sockets formed by the coinciding recesses andforming dowels to preserve the integrity of the spiral web, a shaftpassing through the rings of the cutterhead sections, and clampingdevices for binding the cutter-head sections together on the shaft,substantially as herein set forth.

4. A cutter-head comprising a series of transversely ranging sectionshaving end wings or parts, which, when the sections are clamped togetherface to face, form oppositelyranging or right and left hand spiralsmeeting about at the centerofthe cutter-head, and said wings or parts ofthe sections formed with recesses in their opposite faces coincidingwith recesses in the faces of the wings or end parts of the nextadjacent sections when the sections are disposed to form the reversespiral webs,and teeth or cutters having tangs fitting the sock etsformed by the coinciding recesses and forn1- ing dowels to preserve theintegrity of the reverse spiral webs when the cuttenhead sections areclamped together, substantially as herein set forth.

5. A cutter-head comprising a series of transversely ranging sectionshaving end wings or parts radiating from a central ring or collar, andadapted, when the sections are clamped together face to face, to formoppositely-ranging or right and left hand spirals meeting about at thecenter of the cutter-head, and said wings or end parts formed withrecesses in their opposite faces coinciding with recesses in the facesof the wings or end parts of the next adjacent sections when thesections are disposed to form the reverse spiral webs, teeth or cuttershaving tangs fitting the sockets formed by the coincidingface recesses,said tangs forming dowels to preserve the integrity of the reversespiral webs, a shaft passing through the rings of the cutter-headsections, and clamping devices for binding the sections together on theshaft, substantially as herein set forth.

6. In sectional spiral cutter-heads, the combination,with the sectionsB, having end wings or parts adapted to form a spiral web when thesections are clamped together face to face, and provided withcoinciding-face recesses E F, substantially as specified, of teeth orout ters having tangs fitting sockets formed by said coincidingrecesses, and also having body portions which overlap and mutuallysupport each other laterally, substantially as herein set forth.

7. In sectional spiral cutter-heads, the sections B, formed with acentral ring, I), opposite end wings or parts, B B, having beveled edgesIf I), and formed with recesses E F in their opposite faces I) I)", andsaid recesses having notches G, adapted to interlock with projections onthe cutters, substantially as herein set forth.

8. In sectional spiral cutterheads, the combination,with the sectionsB,having end wings or parts, B, recessed at E F and notched at G, of theinsertible cutters or teeth having tangs I, provided with teeth orprojections H, adapted to the notched recesses E F G, substantially asdescribed, whereby the cutters will be retained in place againstcentrifugal force and may be projected when worn, as set forth. V

9. A spiral cutter-head composed of sec lions B, formed with a centralring, I), opposite end wings or parts B 13, having beveled edges I) I),and formed with recesses E F in their opposite faces, adapted to receivetangs on the cutters, substantially as herein set forth.

10. A sectional, spiral cutter-head the teeth W. H. WVooD, CHAS. G.SCHRAMM.

